Means for fastening cutting dies on a base plate

ABSTRACT

A die is secured to a base plate by a resilient yoke which has hooks engaging recesses in the base plate. This mode of fastening permits the die to yield somewhat in the lateral direction and hence promotes automatic adjustment of adjacent knives.

1mm Sfiates Patent [1 1 [111 3,739,676 Gerdin 1 June 19, 1973 MEANS FOR FASTENING CUTTING DIES ON A BASE PLATE [56 References Cited [75] Inventor: Yngve Gerdin, Mjallom, Sweden UNITED STATES PATENTS 3,373,643 3/1968 Spengler 83/698 X [73] Asslgnee' 2:132: Akuebolag Sandv'ken 3,354,766 11/1967 Daalderop 83/698 x [22] Filed: 1 1 Primary EJraminer Willie G. Abercrombie [211 App] No 206 801 Attorney-Ralph E. Parker and Eugene J. Roberts [57] ABSTRACT 30 F P orelgn App canon Horny Data A die is secured to a base plate by a resilient yoke Dec. 14, Sweden has hooks g g g recesses in the base plate This mode of fastening permits the die to yield some- What in the lateral direction and hence promotes auto [58] Field O i S Ql L I QIT........:::: /65 691 694 mafic adjustment adjacent knives 83/684 2 Claims, 4 Drawing Figures MEANS FOR FASTENING CUTTING DIES ON A BASE PLATE This invention relates to cutting dies, and is concerned with resiliently securing a die to a base plate.

For punching figures from a sheet shaped material a number of cutting dies, each forming a closed figure, are mounted on a base plate. It has proved difficult to make a fastening which is easy to connect and disconnect for-replacing and moving the dies. It has also been a problem to prevent the dies from being deformed by material that becomes wedged between adjacent dies.

The invention aims at a solution of these problems by means of a resilient snap device which presses the dies against the base plate. The invention will be more specifically described in the following specification with drawing figures showing:

FIG. 1, cross section of a fastening device according to the invention.

FIG. 2, a section on line 2-2 in FIG. 1.

FIG. 3, a section on line 3-3 in FIG. 1.

FIG. 4, the same fastening device seen from the cutting edge side of the knife.

The cutting die is attached to the base plate 11 by means of a yoke consisting of a spring 12 and two hooks l3 riveted thereto. The spring bears against a tie member 14'on the die 10 and the hooks enter into holes 15 in the base plate, said holes having wider portions 16 at the bottom side of the plate for catching engagement of the hooks. The wider portion 16 is so deep that there is room for the head of the hook in it. The yoke forms a unit that is separate from the die, and thus the die is free to move somewhat laterally in all directions and also to be somewhat turned around an axis perpendicular to the base plate at the same time asit is held in contact with the base plate by the pressure of the 2 spring 12.

The hooks comprise an upper portion 17 having a greater diameter than the holes 15 and a lower portion 18 having a smaller diameter than the holes 15. The portion 18 has at its lower end a laterally extending projection 19 which engages the wider portion 16. As is indicated in FIG. 1, these projections 19, 19 preferably extend in opposite directions with regard to each other, for ready dislodgement. On the inside of portion 17 there is a bevel 20 serving to provide a better grip for detaching the yoke 12, 13. This is preferably performed by means of a tool that is similar to a pair of tongs with outwardly moving jaws which simultaneously act on the surface 20 on both hooks 13.

The holes 15 are arranged in a pattern forming the comers of a regular hexagon so that the yoke can be placed in any pair of diametrically opposed holes in the hexagon. This makes it possible to orientate the die in an arbitrary direction around an axis perpendicular to the plate. Of course other patterns of holes can be used for the same purpose.

The described fastening device renders the die yieldable in the lateral direction, so that adjacent knives adjust themselves automatically in relation to one another and the lateral forces between them are eliminated. The device is also easy to attach and to detach.

I claim:

1. Means for fastening cutting dies on a base plate, comprising a resilient yoke with one hook at each end, said hooks engaging recesses in the plate, the intermediate portion of the yoke acting on the die, urging it resiliently against the plate.

2. Means as defined in claim 1 in which the yoke bears against a tie member of the die. 

1. Means for fastening cutting dies on a base plate, comprising a resilient yoke with one hook at each end, said hooks engaging recesses in the plate, the intermediate portion of the yoke acting on the die, urging it resiliently against the plate.
 2. Means as defined in claim 1 in which the yoke bears against a tie member of the die. 